This invention relates generally to golf putters and, more particularly, to improvements in golf putter shafts, heads and their cooperative interrelationship.
Putting is one of the most important aspects in the game of golf. A golfer's ultimate objective in putting is to strike the ball with the putter head aimed correctly, and with a force, such that the ball travels in the desired direction for a desired distance. A golfer strives to develop his or her putting technique to accomplish this objective repeatedly.
It is generally recognized that it is important to eliminate excessive wrist action from the putting stroke, i.e., a firm-wristed stroke which is made basically with the arms and shoulders is desired. An arm and shoulder stroke with little or no wrist action ensures that the putter face will move through a wider arc so that the face of the club is kept close to the ground and travels horizontally and travels a longer distance along the desired target line. A firm wrist will also help keep the face of the putter head square, i.e., perpendicular, to the target line. However, many golfers have a tendency when putting to jab at the ball using a short wristy movement in which the arms and shoulders are kept still and only the wrists hinge. It is generally considered more difficult to putt accurately using this technique.
It is also important when putting for the ball to be struck by the "sweet spot" of the putter head. The sweet spot is the area on the ball-striking service of the putter head which should come into contact with the ball in order to give the greatest, most reliable and straightest distance to the ball and the best "feel". The sweet spot is usually a relatively small area on the ball-striking surface surrounding the intersection of a straight line normal to the ball - striking surface which also passes through the center of percussion of the club comprising the putter head, shaft and hosel.
When the ball is struck by the sweet spot of the ball-striking surface, the putter head will generally not twist or deviate on contact from its intended orientation square to the desired direction of travel, and the putt will start off in the direction in which the ball-striking surface was aiming. However, if the ball is struck at a point of the putter head off-line from the sweet spot towards the toe of the head, the putter face tends to open and conversely, if the ball is struck off-line towards the heel of the head, the putter face tends to close. In either case, the line along which the ball was to be hit is lost.
While a reduction in wrist action and accurate positioning of the sweet spot of the putter head upon impact will improve the accuracy of the direction in which the ball travels, golfers are always striving to develop a "feel" or "putting touch", i.e., an ability to hit the ball at exactly the right it speed to make the ball travel the distance required, no more, no less. A good putting touch or feel allows the golfer to respond to different textures and moisture conditions of greens as well as general geographical putting conditions, such as putting uphill, downhill, or sidehill.
A development of a putting "feel" depends to a great extent on the ability of the golfer to sense or feel the force that acts on the putter in reaction to the force imparted by the putter head to the ball when it is struck. A good reaction force sensitivity enables the golfer, by trial and error, to learn how hard to hit the ball for any given putting condition. Reaction force sensitivity in turn depends on a number of factors.
First, when the ball is struck by the sweet spot of the ball-striking surface, the magnitude of the reaction force is more easily sensed by the golfer than if the ball is struck off-center and the number of erroneous force vectors is reduced. Moreover, it follows that if the ball is not always struck by the sweet spot, it will not always be struck exactly the same distance from the sweet spot, and the amount of force imparted will vary with every stroke making it impossible for the golfer to learn to judge distance. Second, a good overall reaction force sensitivity also depends on how sensitive the golfer's hands are to "feeling" the relatively low level vibrations indicative of the reaction force. A lightly held putter generally improves hand sensitivity and improves kinesthetic feedback. Unfortunately, it is a natural tendency for many golfers to tightly grip the putter thereby reducing hand sensitivity. Third, the putter's "transmissibility" of reaction forces also affects the overall reaction force sensitivity of the putter. Most conventional putters are constructed in a manner such that the transmission of the reaction force from the putter head to the grip portion of the shaft is absorbed or dampened as it travels through the shaft and grip. For this reason, reaction force transmission of most putters is not good which in turn increases the difficulty for most golfers to develop an accurate respectable putting touch.
The construction of the putter head itself is yet another important factor that can influence putting proficiency. A putter head should accurately translate the force acting on the putter in reaction to the impact of the ball-striking surface on the ball to improve the overall reaction force sensitivity of the club. The location of the center of gravity of the putter head as well as the weight distribution of the head are also important in this regard.